Solve for $x$ and $y$ by deriving an expression for $x$ from the second equation, and substituting it back into the first equation. $\begin{align*}-9x-y &= -2 \\ 9x-9y &= -8\end{align*}$
Answer: Begin by moving the $y$ -term in the second equation to the right side of the equation. $9x = 9y-8$ Divide both sides by $9$ to isolate $x$ $x = {y - \dfrac{8}{9}}$ Substitute this expression for $x$ in the first equation. $-9({y - \dfrac{8}{9}}) - y = -2$ $-9y + 8 - y = -2$ Simplify by combining terms, then solve for $y$ $-10y + 8 = -2$ $-10y = -10$ $y = 1$ Substitute $1$ for $y$ in the top equation. $-9x- 1 = -2$ $-9x-1 = -2$ $-9x = -1$ $x = \dfrac{1}{9}$ The solution is $\enspace x = \dfrac{1}{9}, \enspace y = 1$.